Catalina, the red VT dominant "Queen" has a pie slice chunk gone from her back fin now... :-/
It's a perfect cut, doesn't look like a bite...Or could it be? I hope they aren't rumbling
again! I haven't changed decor or anything. Is it from over flaring?? She flares at everyone during feedings lol

I bet it's a bite. In my community tank, my black phantoms tend to nip at each other sometimes. Their bites always look perfectly triangular. I can't imagine cutting it on decor would cause a pie shaped cut.

Poor girl, keep her water clean and warm. If you're really worried about her, you could quarantine her just in case. When my boy ripped his tail, I switched to using API Stress Coat as my dechlorinator. It helped him heal really quick, and it if you used it, it wouldn't hurt the other girls in your sorority.